[PATCH 4.9 16/56] spi: atmel: fixed spin_lock usage inside atmel_spi_remove

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Radu Pirea <radu.pirea@xxxxxxxxxxxxx>


[ Upstream commit 66e900a3d225575c8b48b59ae1fe74bb6e5a65cc ]

The only part of atmel_spi_remove which needs to be atomic is hardware
reset.

atmel_spi_stop_dma calls dma_terminate_all and this needs interrupts
enabled.
atmel_spi_release_dma calls dma_release_channel and dma_release_channel
locks a mutex inside of spin_lock.

So the call of these functions can't be inside a spin_lock.

Reported-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
Signed-off-by: Radu Pirea <radu.pirea@xxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/spi/spi-atmel.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1669,12 +1669,12 @@ static int atmel_spi_remove(struct platf
 	pm_runtime_get_sync(&pdev->dev);
 
 	/* reset the hardware and block queue progress */
-	spin_lock_irq(&as->lock);
 	if (as->use_dma) {
 		atmel_spi_stop_dma(as);
 		atmel_spi_release_dma(as);
 	}
 
+	spin_lock_irq(&as->lock);
 	spi_writel(as, CR, SPI_BIT(SWRST));
 	spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
 	spi_readl(as, SR);